The invention relates to a primary part or secondary part to a method for producing such a primary part or secondary part, and to a forming die for performing the aforementioned method,
In synchronous motors, it is the primary part with the windings that is cooled; in asynchronous motors, both the primary part and the secondary part can be cooled. The invention also pertains to rotary motors, but preferably to linear motors.
In such a motor, there are slots into which the windings for the coils are inserted. This applies to all types of windings, such as pole windings or windings for generating a migrating field.
As electrical current flows through the applicable windings, heat is generated, which—depending on the power of the motor—must be dissipated by means of suitable provisions for cooling. In the electric motors involved in the subject of the invention, the heat is dissipated by means of cooling tubes which are inserted into the slots below the windings.
For that purpose, it is known to insert a cooling tube into the slots—through the slot opening—before the windings are inserted. Depending on the cross section of the slot, the cooling tube is dimensioned such that it can be simply inserted into the slot and comes to rest on the slot bottom.
The core of the primary part or secondary part comprises a magnetically conductive material, such as stacked laminations, or a solid material in which the appropriate slots are made. In the case of stacked laminations, the laminations are stamped out individually and then joined together into a lamination packet, forming the slots in the process. In the case of solid material, the slots can be milled out, for instance.
Because the cooling tubes are inserted into the slots, the geometry of the slot and the cooling tube is predetermined in such a way that in their installed position, the cooling tubes are disposed on the slot bottom with air between them and the slot wall. Because of the undefined position of the cooling tubes, the windings located above them can contact the cooling tubes only linearly rather than uninterruptedly. This makes the overall cooling performance or cooling efficiency comparatively poor.